Question: what causes the Northen lights to happen?

Emma Davies answered on 21 Jun 2019:

I love this question! The main cause of the Northern Lights are the explosions from the Sun that I study – their proper names are Coronal Mass Ejections, or CMEs for short. These explosions are made up of very hot particles (plasma) and twisted magnetic field. When this twisted magnetic field reaches the magnetic field of the Earth, it can reconnect like two opposite ends of a bar magnet joining together. This process releases A LOT of energy, and the hot particles are briefly allowed through Earth’s magnetic field into our atmosphere! Here they interact and bump into the molecules our atmosphere is made of, causing them to release energy in the form of light – this is the Northern Lights we see! Different molecules make different colours – I think Oxygen causes a red colour, and Nitrogen causes the common green colour we see!